Internal combustion engine



Aug. 9, 1955 M. L. CARROLL 2,714,375

INTERNAL COMBUSTION ENGINE Filed Aug. 21, 1952 4 Sheets-Sheet l w 4-5 36 mvsmora Mbrr i5 ZZCarro ZZ ATTORNEYS 9, 1955 M. L. CARROLL 2,714,875

INTERNAL COMBUSTION ENGINE Filed Aug. 21, 1952 4 Sheets-Sheet 2 IN VENTOR Mr 7" i5 ZLC'a/rroZZ ATTORNEYS 9, 1955 M. L. CARROLL 2,714,875

INTERNAL COMBUSTION ENGINE Filed Aug. 21, 1952 4 Sheets-Sheet I5 IN VENTOR .2 9 i5 [AC c2470 ZZ ATTORNEYS g- 9, 1955 M. L. CARROLL 2,714,875

' INTERNAL COMBUSTION ENGINE Filed Aug. 21, 1952 4 Sheets-Sheet 4 INVENTOR Morris [1. Carroll ATTORNEY5 United States Patent O 2,714,875 INTERNAL COMBUSTION ENGINE Morris Lee Carroll, San Antonio, Tex. Application August 21, 1952, Serial No. 305,535 1 Claim. (Cl. 121-50) This invention relates to internal combustion engines.

An object of this invention is to provide an internal combustion engine embodying an outer cylinder with a pair of concentric pistons and means for effecting opposite movement of the pistons so that the full power impulse will be utilized in operating the drive shaft.

Another object of this invention is to provide in an engine of this type circular cams secured to the drive shaft with a thrust roller on the inner piston so as to transmit the power thrust of the inner piston to the periphery of the inner piston cam.

A further object of this invention is to provide an internal combustion engine which will operate on the two cycle principle while at the same time the outer piston forms the suction means for drawing in the combustible charge and forcing the charge under compression into the outer piston wherein the charge is again compressed between the heads of the inner and outer pistons and then exploded.

With the above and other objects in view, my invention consists in the arrangement, combination and details of construction disclosed in the drawings and specification, and then more particularly pointed out in the appended claim.

In the drawings:

Figure 1 is a detail end elevation of an internal combustion engine constructed according to an embodiment of this invention,

Figure 2 is a sectional view taken on the line 2-2 of Figure 1,

Figure 3 is a sectional view similar to Figure 2, showing the pistons in oppositely disposed position relative to Figure 2,

Figure 4 is a sectional view taken on the line 4-4 of Figure 3,

Figure 5 is a fragmentary sectional view taken on the line 5-5 of Figure 3,

Figure 6 is a fragmentary sectional view taken on the line 6-6 of Figure 5,

Figure 7 is a fragmentary sectional view taken on the line 7-7 of Figure 4.

Referring to the drawings, the numeral 10 designates generally a cylinder which is formed of a cylindrical side wall 11 and an upper head 12. The side wall 11 is provided at the lower end thereof with a flange 13 which is secured to the top wall 14 of a crank case generally designated as 15 by fastening devices 16. The crank case 15 is provided with opposite end walls 17 and 18, and a shaft 19 is journalled through the end walls 17 and 18. An outer hollow piston 20 is slidable in the cylinder 10 and is formed of a cylindrical side wall 21 with an upper head 22.

The cylinder 10 is formed adjacent the upper end thereof with a combination compression and intake chamber 23, and is formed with an intake port 24. An inwardly opening spring-pressed intake valve 25 is carried by a valve housing 26 which is secured to the cylinder 10 and communicates with the intake port 24. The cylinder 10 is also 2,714,875 Patented Aug. 9, 1955 formed with an exhaust port 27 below the intake port 24, and a spark plug 28 is secured to the cylinder 10 and projects into an opening 29 formed in the side wall 11.

The outer piston 20 is formed in the side wall 21 thereof with two or more intake ports 30, and the side wall 21 is also formed below the intake ports 30 with an exhaust port 31. Exhaust port 31 is adapted at the time piston 20 is at the upper end of its stroke to register with cylinder exhaust port 27.

Shaft 19 has secured thereto a pair of circular cam members 32 which are each formed with inner circular cam grooves 33. The lower end of the outer piston 20 has secured thereto a pair of oppositely extending studs 34 which rotatably engage in the cam grooves 33. An inner piston 35 is slidable in the outer piston 20 and is provided at the lower end thereof with a pair of confronting studs 36 which engage in circular cam grooves 37 carried by an intermediate circular cam 38. Cam 38 is fixed to shaft 19 and cam 38 is oppositely disposed with respect to the earns 32 so that the two pistons 20 and 35 will move in opposite directions.

Inner piston 35 also has a roller 39 mounted on a roller shaft 40 which extends diametrically across the inner piston 35. Roller 39 engages the periphery of cam 38 and is provided at the opposite ends thereof with bevelled flanges 41 which engage bevelled edges 42 formed at the opposite ends of the cam 38.

As shown in Figure 6 the studs 34 are formed as rollers, including a cylindrical member 43 having a cylindrical bearing sleeve 44 loosely mounted thereon. Studs 36 are also formed after the manner of studs 34 and include an inner bearing sleeve 45 with an outer bearing sleeve 46. The roller 39, with the bevelled flanges 41 forms a thrust means for taking up the thrust of the inner piston 35, and endwise thrust is taken up by the bevelled flanges 41 and the bevelled edges 42.

In the use and operation of this engine, the fuel is drawn into the intake and compression chamber 23 above the piston head 22 when outer piston 20 is moving downwardly. At the time outer piston 20 is moving downwardly, inner piston 35 is moving upwardly on the compression stroke thereof so as to compress the fuel between the upper end of inner piston 35 and head 22 of outer piston 20. When the fuel is exploded in the explosion chamber 47 which is formed between head 22 and upper end of piston 35, the two pistons will move in opposite directions. Outer piston 20 will compress the fuel charge in compression chamber 23 until the intake ports 30 register with the compression chamber 23. At this time the inner piston 35 is at the bottom of its stroke, uncovering exhaust port 31 which is at this time in registry with cylinder exhaust port 27, as shown in Figure 3. The incoming fuel entering the intake ports 30 will serve as scavenging means for moving the exhaust gases through the exhaust ports 31 and 27. When the pistons 20 and 35 move downwardly and upwardly respectively, the intake ports 30 will move out of registry with compression chamber 23 and exhaust port 31 will move downwardly out of registry with exhaust ports 27.

I do not mean to confine myself to the exact details of construction herein disclosed, but claim all variations falling within the purview of the appended claim.

What I claim is:

In an engine of the type having a cylinder, a crank case at the lower end of said cylinder, a shaft journaled through said crank case, and a pair of telescopic pistons in said cylinder, means for converting the reciprocating movement of the pistons to rotary movement of the shaft comprising a pair of circular cams on said shaft, said cams having confronting cam grooves, diametrically opposed studs having freely rotatable sleeves thereon carried by the outer surface of the outer one of said pistons engaging in said grooves, an intermediate circular cam on said shaft having cam grooves in the outer faces thereof, diametrically opposed studs having freely rotatable sleeves thereon carried by the inner face of the inner one of said pistons engaging in said last mentioned grooves, a shaft extending diametrically across the interior of said inner piston, a roller on said shaft, said roller having inwardly bevelled flanges, an intermediate circular cam carried by said shaft, said intermediate cam having bevelled edges, and engaging said roller between said bevelled flanges.

References Cited in the file of this patent UNITED STATES PATENTS Daniel Apr. 17, 1906 Thie et a1 Jan. 2, 1917 Reichard Sept. 19, 1922 Omo Sept. 9, 1930 Sholking Jan. 12, 1932 Tucker June 14, 1938 

